My 520 is around 6 months old. The battery life has always been poor (sub 10 hours) but recently its dropped to around 5-6 hours. My usual settings are Bluetooth off / 0% screen brightness (& 15 second timeout) and 3-4 sensors attached. (Radar / Power / Heart / Speed)
Today I did a 2hr:15min ride with 3 sensors (Radar/Power/Heart) no BT and 0% screen and it went from 100% to 60%...
Is the battery dying. Or is it the number of sensors running? I'm seriously considering sending it back to CRC for a warranty/replacement ...